A place like the Right Livers' Rest was bound to draw freaks, same as molasses draws flies. 1935, George Goodchild, chapter 5, in Death on the Centre Court: By one o'clock the place was choc-a-bloc.
Swallowing certain types of poisons may cause excessive salivation. According to the National Library of Medicine, pesticides can cause excessive saliva when they are swallowed. Venom from snake bites or insect stings is another type of poisoning that can cause the malady.
The exact cause is not known. But factors contributing to less saliva production and/or thickened saliva may be risk factors for salivary stones. These factors include: dehydration, poor eating, and use of certain medications (such as antihistamines), blood pressure drugs, psychiatric drugs, and bladder control drugs.